The relatively hard problem of transforming a given set of curves to curves with the same shape can sometimes be reduced to the easier problem of rendering curves parallel. In this paper a group is associated with the given curves, and it is shown that the reduction from the hard problem to the easy problem is valid whenever the group is…

Four criterion-referenced reliability coefficicents were compared to the Kuder-Richardson estimates and to each other. The Kuder-Richardson formulas 20 and 21, the Livingston, the Subkoviak and two Huynh coefficients were computed for a random sample of 33 criterion-referenced tests. The Subkoviak coefficient yielded the highest mean value;…

Using the concepts of conditional probability, conditional expectation, and conditional independence, the main results of the classical test theory model can be derived in a very few steps with minimal assumptions. The present effort explores the possibility that present classical test theories can be further condensed. (Author/RC)

The reliabilities of various observational measures were determined, and the influence of both the number and the length of the observation periods on reliability was examined, both separately and jointly. A single simplifying assumption leads to a variant of the Spearman-Brown formula, which may have wider application. (Author/CTM)

The reliability of a criterion referenced test was defined as a measure of the degree to which the test discriminates between an individual's level of performance and a predetermined criterion level. The variances of observed and true scores were defined as the squared deviation of the score from the criterion. Based on these definitions and the…

The literature on criterion referenced testing is full of discussions concerning whether classical measurement techniques are appropriate, whether variance is necessary, whether new indices of reliability are needed, and the like. What appears to be lacking, however, is a clear and simple discussion of why the problems occur. This paper suggests…

The results of five studies into the characteristics of wrong answers as a class of divergent behavior are presented. The evidence from these studies, when taken in combination, suggests that the tendency of researchers to ignore wrong answers has been a fundamental procedural error of broad scope and serious consequences. Instead of the straight…

A summary is provided of the rationale for questioning the applicability of classical reliability measures to criterion referenced tests; an extension of the classical theory of true and error scores to incorporate a theory of dichotomous decisions; a presentation of the mean split-half coefficient of agreement, a single-administration test index…

The Kuder Richardson-20 Formula is shown to be a special case, where each examinee is given sufficient time to answer each item, of a more general formula where each examinee may not be allowed the necessary time. The formula is extended to allow two scores, knowledge and speed, to be extracted from each examinees test score. Using a sample of 82…

The feasibility of criterion referenced testing is held to be dependent on the tenability of two postulates: (1) that bias can be controlled in a principled manner from one test to the next; and (2) that one mental process measured by such tests may lawfully interact with another. Without the first postulate, criterion scores could not be…

The family of Weibull distributions was investigated as a model for the distributions of response times for items in computer-based criterion-referenced tests. The fit of these distributions were, with a few exceptions, good to excellent according to the Kolmogorov-Smirnov test. For a few relatively simple items, the two-parameter gamma…

This partially annotated bibliography of journal articles, dissertations, convention papers, research reports, and a few books and unpublished manuscripts provides a comprehensive coverage of work on latent trait theory and practice. Documents are arranged alphabetically by author. The period covered ranges from the early 1950's to the present.…

Three approaches to the construction of achievement tests are compared: construct, operational, and empirical. The construct approach is based upon classical test theory and measures an abstract representation of the instructional objectives. The operational approach specifies instructional intent through instructional objectives, facet design,…